Question

Phân tích đa thức thành nhân tử:

a)x.(x-1)+(1-x)^2

b)(x+1)^2-3.(x+1)

c)2x.(x-2)-(x-2)^2

Answer 1

a) \(x\left(x-1\right)+\left(1-x\right)^2\)

\(=x\left(x-1\right)+\left(x-1\right)^2\)

\(=\left(x-1\right)\left(x+x-1\right)\)

\(=\left(x-1\right)\left(2x-1\right)\)

b) \(\left(x+1\right)^2-3\left(x+1\right)\)

\(=\left(x+1\right)\left[\left(x+1\right)-3\right]\)

\(=\left(x+1\right)\left(x+1-3\right)\)

\(=\left(x+1\right)\left(x-2\right)\)

c) \(2x\left(x-2\right)-\left(x-2\right)^2\)

\(=\left(x-2\right)\left[2x-\left(x-2\right)\right]\)

\(=\left(x-2\right)\left(2x-x+2\right)\)

\(=\left(x-2\right)\left(x+2\right)\)